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Essential Questions: What is the cell theory? What are similar functions of all cells?

Quick Action – INB Template Cell Theory Robert Hooke Matthias Schleiden, Theodor Schwann, & Rudolph Virchow Cell Theory INB Template Cut out the Template on the solid lines Glue outside tabs into notebook Opens like windows Write notes underneath window panes What is the cell theory? What are the 2 main types of cells?

Cell Theory Cell Smallest structural and functional unit of an organism Usually microscopic Contains cytoplasm and a nucleus enclosed in a membrane Two main types of cells: 1. Prokaryotic (no nucleus) 2. Eukaryotic (has a nucleus)

Robert Hooke Cell Theory 1665 Observed bark of cork trees under a microscope Thought the objects looked liked individual rooms in a monastery, which were called cells Called his discovery cells Did not know their true function 1665 Cork Cells

Anton van Leeuwenhoek Cell Theory Developed the microscope lens to see greater magnification First person to observe bacteria and protozoa (single-celled animal) Observed and described red blood cells 1670

Mathias Schleiden Cell Theory Concluded all plant tissues are composed of cells Declared that the cell is the basic building block of all plant matter. Sensed the importance of the nucleus of a cell 1838 Plant Cell

Theodor Schwann Cell Theory Concluded that all animal tissues are composed of cells, too. Collaborated with Schleiden to form a new theory in biology 1839 Animal Cell

Cell Theory Cell Theory Schleiden and Schwann’s ideas became known as the cell theory. All organisms are composed of cells. Cells are the basic unit of life. This theory was as important to biology as the atomic theory was to chemistry. There was one more piece of the puzzle to cell theory. Where did these cells come from?

Rudolph Virchow Cell Theory Proposed that all cells result from the division of previously existing living cells This idea became a key piece of the modern cell theory. 1855

Cell Theory Modern Cell Theory All organisms are composed of cells. Cells are the basic unit of life. All cells come from the division of previous existing cells.

Quick Action – Cell Theory That’s a lot of scientists to remember with very long names. Work with a partner and come up with some sort of device to remember the importance of each one in the development of cell theory. Share your creative device with the class. Robert Hooke – named the cell base observations on cork bark Anton van Leeuwenhoek – improved the microscope and observed bacteria and one-cell animals Mathias Schleiden – all plant tissue is made of cells Theodor Schwann – all animal tissue is made of cells Rudolph Virchow – all cells come from preexisting cells

Cell Theory Functions of Cells Metabolism- chemical reactions inside the cell Response – perceiving and responding to changes in the environment Homeostasis – keeping conditions inside the organism within tolerable limits (balanced) Metabolism Response Homeostasis

Functions of Cells (continued) Cell Theory Growth Reproduction Functions of Cells (continued) Growth – increase in size Reproduction – producing offspring (sexually or asexually) Nutrition – Obtaining food to provide energy for growth Defense – protection against enemies Defense Nutrition

Quick Action – Cell Theory Let’s see how good you memory is. There were 7 cell functions listed on the last two slides. Have your teacher give you another peek at them and then write down as many as you can remember.

Check for Understanding Can you… Recognize that according to cell theory all organisms are composed of cells? Recognise that cells carry on similar functions. Clear up any confusion and answer questions.